NixOS allows me to back up all the configuration for my entire complex hypervisor server by just saving one folder, since it centralizes all system configuration in /etc/nixos. That is an absolute godsend.
And that’s just one example, practically any NixOS installation is easily reproducible by just grabbing the configuration files from that folder. It makes configuring a new install a breeze.
I don’t know if I want a project as cool as Proxmox owned by the “you will use snap and you will like it” Canonical